Is a Pumpkin a Squash? Understanding Cucurbitas

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Pumpkins are a distinct part of American culture, especially during fall.
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Neatly stacked ‘Musquee de Provence’ (C. moschata) make for a beautiful display.
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C. pepo squash have five-angled stems that slope smoothly to meet the fruit.
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C. maxima squash have irregularly rounded stems with no angles.
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Native Americans dried strips of pumpkin and wove them into mats. They also roasted long strips of pumpkin on the open fire and ate them. The origin of pumpkin pie occurred when the colonists sliced off the pumpkin top, removed the seeds, and filled the insides with milk, spices, and honey. The pumpkin was then baked in hot ashes.
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One difference between summer and winter squash is that we eat summer squash before the seeds have hardened and the fruit has ripened, while we eat winter squash only after the fruit has matured.

It’s somewhat difficult to come up with a backyard garden crop more a part of American culture than that plump, round, ribbed, vining fruit that we look forward to honoring every fall. Of course, corn makes the world go ‘round — but not sweet corn like you find in the typical backyard garden. Americans also consume about a potato per day on average. And who doesn’t like green beans? Yet all those backyard crops take a back seat each fall as families head into the pumpkin patch, gather around the picnic table to carve jack-o’-lanterns, and in the end enjoy a delicious squash pie at Thanksgiving. Wait … squash?

The simplest maxim is all pumpkins are squash, but not all squash are pumpkins. So what is a pumpkin, and why do we care? Botanists call one particular group of squash, which belongs to one particular species, pumpkins. The species, Cucurbita pepo, differs from all other species of squash in certain characteristics, such as its leaves and stem. The classic orange fruit, whether big or small, round or oblong, is what botanists routinely agree is a pumpkin. Not everyone else, though, is on the same page. Let’s try to get to the bottom of it, shall we?

C. pepo squash include scallop (var. clypeata), zucchini (var. cylindrica), yellow summer squash, the winter varieties of acorn (var. turbinata), pumpkin (var. pepo), and spaghetti squash, among others. One difference between summer and winter squash is that we eat summer squash before the seeds have hardened and the fruit has ripened, while we eat winter squash only after the fruit has matured.

The Domestication of Cucurbita Pepo

Let’s wind back thousands of years. Some 8,000 to 10,000 years ago, Native Americans domesticated C. pepo squash from wild gourds in Mexico. What these squash were really like is unclear, but they may have been cultivated only for their seeds at first and, in some cases, for their hard shells. What we do know is that these first domesticated fruits contained the distinctive orange pigmentation of true pumpkins.

Fast forward four or five thousand years to eastern North America, where a second group of Native Americans domesticated another gourd — the Ozark wild gourd (C. pepo var. ozarkana) — and created a whole new line of C. pepo squash cultivars, possessing green, white, and yellow skin colors and a vast array of fruit types. These all had, and still have, the ability to cross-pollinate with each other. Cucurbita pepo is one of the most variable species in the world for fruit shape. If you let your zucchini cross-pollinate with your acorn squash and grow out the seeds, you’ll see what I mean.

By the time Columbus came to America, Native American agriculture was in full swing, including the extensive cultivation of corn, beans, squash, sunflowers, and Jerusalem artichokes in the eastern section of the continent. The squash species in the northeast was primarily C. pepo, with some cultivation of Cucurbita argyrosperma in the more southwestern reaches of eastern America. The C. pepos had a wide array of fruit types, including what we typically call gourds, similar to the types grown for Halloween today. There were also types of scallop summer squash, acorn winter squash, and our familiar orange pumpkin.

Is a Pumpkin a Squash?

How botanists came to call only the orange fruit “pumpkins” is tied up in history and etymology, and not all of it is clear. Pepo, the specific epithet of pumpkins, also refers to the botanical name of the fruit of all cucurbits, including squash. In Greek, pepon refers to a sun-ripened or “cooked” fruit, which at that time meant Old World watermelon and melons, and in Latin that became peponem or pepo. In Middle French, this became pompon, and in English pompion, then pumpion, and eventually pumpkin or “punkin.” A 19th-century writer speculated the word came from “pump” because growers pumped so much water to grow pumpkins. The term pompion was applied to the Native American C. pepo squashes beginning in the early 16th century. Orange pumpkins were one of the first fruits encountered by explorers and settlers in the New World.

Over time, though, the term pepo and pompion became closely associated with the pepo squash group and pumpkins. The term pompion was used continually in describing the C. pepo squash varieties in North America and northern Europe, although on some occasions it might also refer to melon, watermelon, or even a true gourd (Lagenaria spp.).

Cucurbita Maxima

While botanists stick closely to the original application of the word to describe those ribbed orange fruits, the public does not, so the term has been applied to a wide variety of squash.

The most obvious use of the term “pumpkin” applied to a non-pepo squash is the ‘Cinderella Pumpkin’ (Cucurbita maxima), otherwise known as ‘Rouge vif d’Etampes.’ The C. maxima species originated in South America. The ‘Cinderella Pumpkin’ is a large, strongly ribbed, reddish-orange, flattened squash, vaguely resembling the classic orange pumpkin. It was cultivated in France and introduced in 1883 to the United States. The fruit can weigh up to 35 pounds, and the flesh is thick with good taste. Some claim this is the authentic pumpkin from the fairy tale Cinderella. But in his version of the story popularized in 1697, Charles Perrault added that the carriage turned into a “golden pumpkin,” which seems closer to the bright orange of true pumpkins. According to his version, “Her godmother scooped out all the inside of it, having left nothing but the rind,” which again sounds like a traditional carving pumpkin rather than a thick-fleshed C. maxima squash.

Another orange-skinned cultivar is C. maxima ‘Mammoth’ — also known as ‘Mammoth King Pumpkin,’ ‘Jumbo Pumpkin,’ and ‘Giant Pumpkin,’ among other names. It was known by 1834, and is the largest American cultivar, sometimes weighing more than 50 pounds. It’s globe shaped with orange skin, thick flesh, and buff stripes, vaguely resembling a true pumpkin. The quality was not good, so it was used exclusively as cattle feed. It may have been the leading cultivar for which the terms “squash” and “pumpkin” were used interchangeably.

‘Mammoth’ was also known as ‘Potiron,’ the name of a French cultivar C. maxima ‘Potiron Jaune Gros de Paris,’ which commonly reached 50 to several hundred pounds. While this cultivar may have been synonymous with ‘Mammoth,’ it seems more likely to be a close relative. There were a number of variations of this squash with skin ranging from yellow to salmon color and rinds that were relatively smooth to ribbed. First documented in the 1850s in Europe, it was originally grown in the United States by Henry David Thoreau, who obtained seeds from the U.S. Patent Office in 1857.

During the last few decades, the name pumpkin has been affixed to an offspring of the ‘Potiron,’ the ‘Atlantic Giant Pumpkin,’ bred by Howard Dill, which has produced record-breaking squash, with specimens currently reaching the 2,000-pound range. Giant pumpkin contests are common throughout the country, and this usage of pumpkin has surely added to present-day confusion in terminology.

Many other C. maxima squash may be called pumpkins depending on which seed catalog you’re reading.

Cucurbita Moschata

Cheese “pumpkins” are large, round, flattened, tan-colored squash, which were cultivated in Colonial times and first offered commercially by Bernard McMahon in 1807. They belong to the Cucurbita moschata species, whose ancestors originated in northern South America or Central America about 5,000 to 6,000 years ago. (Butternut is probably the most well-known representative of this species.) A number of variations of the cheese squash exist, although all are fairly similar with prominent ribs and weighing about 6 to 12 pounds. ‘Long Island Cheese’ is one cultivar commonly available, which vaguely resembles the ‘Cinderella Pumpkin.’ Although they tend to be a bit stringy, these squash taste fairly good and are a welcome addition to the dinner table.

Another member of the C. moschata species is the ‘Dickinson Pumpkin,’ a cultivar originating in the Southeast around 1835 and brought north to Illinois by Elijah Dickinson. This is an oblong ribbed squash weighing 30 to 40 pounds with smooth, thick flesh. The ‘Dickinson Pumpkin’ is the squash most of us consume in pies and other products because most of the U.S. production of “pumpkin” filling is from this cultivar.

The C. moschata crookneck (also called long neck) resembles a giant butternut with a prominent, elongated, and often curving neck. Unlike the aforementioned squashes, this one doesn’t even vaguely resemble a pumpkin. As with the ‘Dickinson Pumpkin,’ it may have gotten its name because it was supposedly used by the Amish in Pennsylvania to make pies. The flesh is thick, smooth, and tasty.

Cucurbita Argyrosperma

Pumpkin is also a name applied to a fourth species of squash, Cucurbita argyrosperma. These are the cushaws, or cashaws, and are represented by cultivars such as ‘Green-Striped,’ ‘Tennessee Sweet Potato,’ ‘Golden Cushaw,’ and forms of ‘White Cushaw.’ These were used for pies in the 19th and early 20th centuries. They sometimes had “pumpkin” affixed to their name or were considered pumpkins in catalogs and cookbooks. Having never grown these in a hot climate, I can’t vouch for their quality.

Whether you call a pumpkin a pumpkin, a squash a pumpkin, or a squash a squash, just remember that most of your fellow citizens have probably never tasted a real pumpkin pie. If you want to try a “pepo pumpkin” this fall, reach for C. pepo heirlooms, such as ‘Connecticut Field,’ ‘New England Sugar Pie,’ and ‘Winter Luxury Pie,’ as well as modern cultivars, such as ‘Howden,’ ‘Spookie’ — also known as ‘Spookie Pie’ or ‘Deep Sugar Pie’ — and others.

So, there you have it. Around the holidays, when you reach for that slice of “pumpkin” pie and casually ask, “Is this a pepo pumpkin?” — just know the conversation could get a little dicey.

Ethnobotanist and former director of the Eastern Native Seed Conservancy, Lawrence Davis-Hollander gardens, cooks, and — at a nearby preserve — watches bald eagles and seasonal wildflowers.

Mother Earth Gardener
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